/Engine/Source/Runtime/Engine/Classes/Engine/ViewportSplitScreen.h
Various data declarations relating to split screen on a GameViewportClient
namespace ESplitScreenType { enum Type { None, TwoPlayer_Horizontal, TwoPlayer_Vertical, ThreePlayer_FavorTop, ThreePlayer_FavorBottom, ThreePlayer_Vertical, ThreePlayer_Horizontal, FourPlayer_Grid, FourPlayer_Vertical, FourPlayer_Horizontal, SplitTypeCount, } }